The present invention relates generally to vessels provided with a refractory lining which are particularly suitable for shipment of liquid metals such as pig iron and which are provided with detachable cover means including fastening elements distributed about the periphery of the vessel.
Vessels of the type to which the present invention relates are normally used for pig iron mixers wherein a cylindrical shell has an annular flange at one or both ends upon which there is secured by means of screws or other similar devices a cover or bottom member. However, such conventional screw joints for fastening covers to such vessels involve a disadvantage in that they are difficult to loosen and detach if the threads become damaged or inoperative. Furthermore, manufacturing requirements of high precision are involved due to the necessity for enabling the covers to be interchanged. If flange holes and other connecting members are not accurately located relative to each other, disconnection and replacement of cover members can involve substantial difficulty. The precision with which flange holes and other connecting devices can be made to coincide during assembly and use of the devices encounters obstacles due to the fact that when the vessel is in use unavoidable heat factors cause misalignments to occur thereby rendering assembly and disassembly more difficult.
The present invention is aimed at overcoming problems involved in the aforementioned type of vessels and toward avoiding many of the difficulties which might arise when cover members are to be quickly attached and detached, for example, during relining of the vessel. The invention is intended to provide an improved vessel construction of the aforementioned type wherein many of the problems encountered with prior art structures may be obviated or significantly alleviated.